(num_sign_bit_copies): At end, return 1 if NONZERO has the high bit set.

From-SVN: r4627

diff --git a/gcc/combine.c b/gcc/combine.c
index 5ac961f184c3974e2cf1c01002c603e282d81748..7aa534879f5bc1a7babcee0c10a1377538c7c5eb 100644 (file)
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -6801,7 +6801,7 @@ num_sign_bit_copies (x, mode)
     return 1;
 
   nonzero = nonzero_bits (x, mode);
-  return (nonzero == GET_MODE_MASK (mode)
+  return (nonzero & ((HOST_WIDE_INT) 1 << (bitwidth - 1))
          ? 1 : bitwidth - floor_log2 (nonzero) - 1);
 }
 \f